Green leader Natalie Bennett branded UKIP’s immigration-centred posters “dangerous” as her party launched its campaign for the European elections in the eastern region.

UKIP has faced criticism for a £1.5 million publicity drive which will see warnings posted on billboards that 26 million unemployed people across Europe are “after” British jobs and, at an event in Cambridge, Greens said they offered a positive alternative.

Ms Bennett said the posters were a “disgrace”.

She said: “What this will do is empower the drunk man in the pub and the irate woman on the bus to lash out at anyone they see to be an immigrant and this will make us a more dangerous, divided society, and we must stand up to this.

“This is where we as Greens have to lead, because we are entirely missing out on leadership from the three largest parties.

“The three largest parties, instead of standing up to UKIP and saying that’s dangerous, they have been chasing after UKIP seeing if they can ‘out-UKIP’ UKIP on immigration.”

Ms Bennett said a Green MEP for the East would push for the European Union to be reformed so it worked for the good of everyone, not a few – and she argued winning a seat was a real possibility, with a swing of just 1 per cent needed from the 2009 polls.

Lead candidate Rupert Read said the party’s campaign would focus on pushing for greener transport, greener energy generation, and tackling the scandal of soaring food bank use.

Dr Read said he expected the UKIP vote to go up in the East, but that the Greens could benefit from a collapse in support for the Liberal Democrats, while also picking off former Conservative and Labour supporters.

He said: “It wouldn’t be surprising if the vote for UKIP goes up, but what are these people voting for?

“They know what they are voting against. They are voting against immigrants, they are voting against the EU, they are voting against the political establishment, they imagine – but they are not taking into account that Nigel Farage is a public school-educated stockbroker backed by multi-millionaires.

“We are offering a positive vision and our hope and belief is that enough people will turn to something positive to get us at least the one seat we want to win at this election in the eastern region and more across the country.”

The posters have been defended by UKIP leader Nigel Farage, who said they were a “hard-hitting reflection of reality as it is experienced by millions of British people struggling to earn a living outside the Westminster bubble”.

The Greens say they don’t want to walk away from Europe – they want to change it from within.

Policies in the party’s manifesto for the Eastern region include:

• Increasing the Europe-wide carbon dioxide emissions reduction target to 60 per cent initially, and 90 per cent by 2030, with binding renewable energy targets for all member states;

• Investment in green technologies such as insulation and renewable energies such as solar and wind power;

• Returning the railways to public ownership and revive regulation of local bus services;

• Introducing an Oyster-style pay-as-you-go payment card for trains;

• Using European money to invest in cycling, walking and car sharing;

• Ending laws which discriminate against part-time workers;

• Supporting small businesses, social enterprises and cooperatives

• Splitting banks between retail and investment arms; and

• Rejecting a blanket idea of a ‘North Atlantic alliance’ and launching military action on a case-by-case basis only.